In the embodiments provided herein, there is disclosed a portable, simple, safe and reliable spark plug testing kit for utilisation on small petrol engines. For example, the spark plug testing kit may be stored on a toolbox or the like and utilised where and when necessary such as, for example, problem solving a recalcitrant lawnmower.
The conventional problem-solving approach for small petrol engines is to remove the spark plug and place the spark plug on the engine block to form a ground connection whereafter the engine is cranked to view the spark within the spark gap of the spark plug. Such an approach is dangerous in that fuel may be inadvertently ignited, the operator electrocuted and/or debris falling into the combustion chamber via the spark plug opening.
As such, the spark plug testing kit according to the embodiments described herein allows for safe and convenient testing of petrol engines which eliminates or substantially ameliorates these problems while allowing for the clear and simple inspection of the spark of the spark plug. As will be appreciated from the ensuing description, the spark plug testing kit offers advantages in light of existing practices and arrangements in portability, ease-of-use, reliability and safety.
In this regard, turning now to FIG. 1, there is shown a prior art arrangement as is disclosed in U.S. Pat. No. 4,570,124 A (Fuchs) (hereafter D1) which is considered as the closest art. D1 discloses a portable self-contained ignition system test diagnostic instrument for testing single cylinder and multi-cylinder spark ignited engines having an transparent spark chamber for visual inspection of a spark plug spark and an air pump for pressurising the spark chamber so as to visually inspect the spark plug and a differing pressures.
Specifically, as is disclosed in D1, to test a single cylinder engine, the ground wire 38 is connected by the test clip 40 to any suitable ground point on the engine. The spark plug wire is removed from the engine spark plug and mounted on the upper terminal 76 of the test spark plug 32. The spark plug is removed from the engine and the engine is cranked with a rope or electric starter wherein the ignition spark arc is visually observed through the transparent housing.
However, D1 suffers from several disadvantages including safety. For example, the removal of the spark plug allows potentially engine damaging debris from falling into the cylinder chamber.
Furthermore, the utilisation of the crocodile clip 14 connected to any suitable ground point on the engine is not reliable in that it does not always form a reliable electrical connection thereby potentially affecting the spark and is furthermore inconvenient to use in having to find and locate a suitable attachment point.
Furthermore, the electrical leads of D1 are exposed which may inadvertently result in the 19 kV electrocution of the operator.
Furthermore, turning now to FIG. 2, there is shown a further prior art arrangement as is disclosed in U.S. Pat. No. 1,695,557 (Myers) (hereafter D2) discloses a device having a plurality of openings for receiving spark plugs therein for the purposes of testing the spark plugs at high air pressure. The device comprises a mirror for taking observations so as to reduce risk of injury in the event of glass blow out from residual gasoline explosion.
However, D2 is a “high-end” laboratory testing device suited for testing multiple spark plugs simultaneously being dissimilar from the portable and simple testing kit as is disclosed herein. Furthermore, D2 comprises inbuilt transformers, spark coils and the like for the purposes of powering the spark plugs. Furthermore, D2, in incorporating inbuilt electrical componentry, is incapable of testing the electrical distribution system/magneto and the like of the actual engine while simultaneously testing the spark plug.
Turning now to FIG. 3, there is shown a further prior art arrangement as is disclosed in U.S. Pat. No. 3,360,718 (WILLIAMS) (hereafter D3) which discloses a spark plug tester in which all of the plugs for an internal combustion engine can be simultaneously laid in an up-ended inclined position upon contacts on a tray for selective electrical testing within a pressurized housing. However, D3 is not dissimilar from D2 in the construction and arrangement thereof being suited for a laboratory environment, or and including in the incorporation of inbuilt electrical componentry and the like and is therefore not suited for testing of a spark plug in conjunction with the electrical distribution system of the actual engine itself as can the spark plug testing kit of the present embodiments disclosed herein.
As such, neither D2 nor D3 are capable of testing the electrical distribution system of the actual engine while simultaneously testing the spark plug.
As will be described in further detail below, the spark plug testing kit of the present invention comprises componentry that confers advantages in portability, simplicity, safety and reliability as compared to prior art arrangements.
Specifically, and as will be described in further detail below, the spark plug testing kit comprises an enclosed and transparent spark plug observation device. The spark observation device may be handheld in distinction to the arrangements disclosed in D2 and D3 so as to provide a clear view of the spark gap.
Now, the spark plug observation device is sealed for safety so as to prevent inadvertent ignition of gasoline vapour. In this regard, it is noted that the observation chambers of D2 and D3 do not prevent gasoline explosions but rather mitigate against injury from flying glass through the utilisation of mirrors.
The spark plug testing kit of the present embodiments further comprises a spark plug opening engaging device which may serve three purposes when engaging the spark plug opening in 1) allowing the depressurisation of the chamber so as to facilitate cracking, 2) preventing debris from entering the spark plug opening and 3) providing a secure electrical connection for the ground lead of the spark plug testing kit. Furthermore, in embodiments, the spark plug opening engaging device comprises a spark plug-type electrical terminal head allowing for the connection thereto utilising a conventional insulated spark plug connector and associated insulation boot.
As alluded to above, D1 utilises a crocodile clip 40 for the purposes of forming a ground connection to the engine block being tested.
However, the crocodile clip 40 of D1 does not provide a reliable electrical connection. Conversely, the spark plug opening engaging device forms a superior electrical connection not only with the engine block but also the earth electrical lead connected to the spark plug type terminal head.
Furthermore, the testing kit of D1 may allow debris to inadvertently enter the combustion chamber during testing and therefore damage the engine.
Furthermore, the spark plug opening engaging device provides an exhaust passage allowing the depressurisation of the chamber while being engaged within the spark plug opening to as to ease cranking.
In this regard, U.S. Pat. No. 3,115,033 A (Williams) (hereafter D4) discloses an internal combustion engine compression testing device configured for insertion into the spark plug opening of a cylinder and comprising a pressure gauge for compression testing.
However, D4 is directed to compression testing, not electrical testing of an engine and a skilled person could not be have reasonably been expected to combine the disclosures of D1 and D4 together given these differing and distinct skill sets. In this regard, it could generally be argued that engine compression testing and engine electrical systems would more likely be maintained by differing types of skilled persons having ordinary skill.
Furthermore, assuming that the skilled person would have sought to have improved the electrical connection of the earth lead 38 of D1, it could only be said that the hypothetical routine steps of the skilled person would extended only so far as to enhancing the electrical connection of the crocodile clip 40, such as by utilising another type of clip or engagement.
Furthermore, it could not be reasonably be expected for the skilled person to have sought to blocked or otherwise engaged the spark plug opening because the problem of debris falling into the chamber is not even recognised by the prior art on record (as is evidenced by the discloses of D1-D4). As such, it could not have been expected for the skilled person to have arrived, by routine steps alone, to a testing kit comprising the spark plug opening engaging device of the present arrangement is configured to prevent debris from falling into the chamber.
Furthermore, even assuming that the person skilled had arrived at the utilisation of a spark plug opening engaging device, it could not have been reasonably expected for such spark plug opening engaging device to have an exhaust to allow for the decompression of the chamber to ease cranking cranking.
Furthermore, and as also be appreciated from the ensuing description, the spark plug testing kit of the present arrangements provides further advantages in portability, safety and reliability as compared to prior art arrangements including prior art references D1-D4.
Specifically, as will be seen from the ensuing description, the spark plug testing kit is electrically isolated to prevent inadvertent shock to the user. Furthermore, the testing kit is able to be dismantled for the purposes of installation and removal wherein, during the installation stage, the spark plug is removed, the spark plug opening engaging device is inserted into the spark plug opening and tightened with a socket whereafter the spark plug is inserted into the observation device and whereafter the earth lead electrical connection boot is inserted over the distal terminal of the spark plug opening engaging device and further where after a terminal of the positive lead is inserted into the connector from the distributor. Furthermore, the spark plug observation device is able to be screwed together so as to isolate the spark from flammable liquids vapours and the like.
As such, as can be appreciated, the prior art, including that which is disclosed in references D1-D4 neither discloses nor suggests a testing kit arrangement comprising the features and functionality of that which is disclosed in accordance with the present embodiments.
It is to be understood that, if any prior art information is referred to herein, such reference does not constitute an admission that the information forms part of the common general knowledge in the art, in Australia or any other country.